German Patent No. 44 19 813 A1 describes an apparatus for operating an electric motor, stepping motor, or commutator motor, which analyzes an overload or jamming of the drive system for which the electric motor is the power source based on a parameter of a current flowing through the electric motor. The parameter can be determined either within a time interval which still lies within the activation operation after a starting time of the electric motor, or at a predefined sampling time which lags the starting point by a certain delay time. The parameter used for the current being analyzed can be the current amplitude, the change in current, or a current difference, which is evaluated as the signal for the stop and jamming detection system. It is essential in this conventional apparatus that the electric motor be at least approximately current-free at the beginning of the aforesaid starting point, and that the time interval or sampling time occur before steady-state motor current is reached.